Help Identifying Algae & Tips

[Dustinc1983]

Hello,

I have a basic set up that's been up and running for 15 months. 20 gallon tall tank, Orbit Marine LED 24", Eheim 100w heater (77 degrees), Fluval (Aquaclear 50) filter running floss and chemipure elite and a bag of biomax media, as well a hydor Nano 425 powerhead.

I do 2.5 gallons of water change a week, I buy my water premixed at my local reef store (Elite Reef) and they use Kent salt premix. I top off with RO Water which I purchase as well. Regular basic testing for Phosphate, Ammonia, Nitrate, Nitrite, pH, Alk and Calcium and Salinity with a cheap Amazon refractometer. Always within limits and stability.

The pictures I have are with pure white leds running only for help with my question. Any thoughts ? I assume it’s a dead flow area .. best to just suck that up? Also, it’s much worse during the day and tends to look less “ugly” in the morning before my lights come on.

Thanks

 

[RJinPV]

It looks and sounds like a blue green cyano bacteria. Does it easily dislodge from the gravel if you blow on it with a turkey baster? If it is blue green cyano then increased flow should help. Do you know what is in your RO water used for topping off the tank? If it is RO, not RO/DI water, it could have 10 to 30 ppm of bad stuff in it, like phosphates, and feed the problem. Do you have a TDS meter?

 

[Dustinc1983]

Thanks, yeah it easily comes off even with a small airline hose ...

My mistake on terminology, It’s RO/DI water that I use and no TDS meter. I should ask my local store to see their results maybe.. I exclusively use their water.

Maybe I’ll try another power head too

 

[Dustinc1983]

Just sucked all that gunk up.. comes up super easy. It’s oddly satisfying.

Did 25% water change (5 gallons)

Testing as of today is 8.0/8.1 ph, NO2 0, NO3 o, PO4 0, 1.025 salinity.

Anything else worth testing?